GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Headlights System Check?

--

Go to Step 2

Go to Headlight System Check

2

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the headlamp switch connector.

Do the headlamps turn off?

--

Go to Step 8

Go to Step 3

3

Disconnect the headlamp dimmer switch connector C202.

Do the headlamps turn off?

--

Go to Step 11

Go to Step 4

4

Disconnect the lamp control module (LCM) connector C2.

Do the headlamps turn off?

--

Go to Step 7

Go to Step 5

5

Disconnect the LCM connector C1.

Do the headlamps turn off?

--

Go to Step 9

Go to Step 6

6

Repair the short to battery positive voltage (B+) in CKT 12 (TAN). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--

7

Test CKT 103 (WHT) for a short to ground. Refer to Testing for Short to Ground in Wiring Systems.

Is there a short to ground in CKT 103?

--

Go to Step 10

Go to Step 12

8

Replace the headlamp switch.

Is the headlamp switch replacement complete?

--

Go to Headlight System Check

--

9

Replace the LCM. Refer to Headlamp Control Module Replacement .

Is the LCM replacement complete?

--

Go to Headlight System Check

--

10

Test CKT 307 (YEL) for a short to ground. Refer to Testing for Short to Ground in Wiring Systems.

Is there a short to ground in CKT 307?

--

Go to Step 9

Go to Step 12

11

Replace the headlamp dimmer switch. Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Wheel and Column-Tilt

Is the headlamp dimmer switch replacement complete?

--

Go to Headlight System Check

--

12

Repair the faulty wiring. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Headlight System Check

--